Articulated joint



1969 a. FONDA-BONARDI 3,

ARTICULATED JOINT Sheet Filed Sept. 10. 1965' INVENTOR. G/us To Fomm B 010090! 1969 s. FONDA-BONARDI 3,421,158

ARTICULATED JOINT Filed Sept. 10, 1965 Sheet Z of 55 G/us TO FomamBounen/ INVENTOR.

1969 G. FONDA-BONARDI 3,421,158

ARTICULATED JOINT Sheet 3 of Filed Sept. 10, 1965 3 36 49 52 G/uSTo F0 58 l N VEN TOR. NM BONQQDI United States Patent 3,421,158 ARTICULATED JOINT Giusto Fonda-Bnnardi, Los Angeles, Calif., assignor to Litton Systems, Inc., Beverly Hills, Calif. Filed Sept. 10, 1965, Ser. No. 486,474 US. Cl. 2-2.1 25 Claims Int. Cl. B63c 11/04; F61] 27/10; F161 19/00 ABSTRACT OF THE DISCLOSURE An articulated joint for interconnecting to portions of a deep sea diving suit which is adapted to enclose adjacent members of the human body, comprising a plurality of substantially spherical segments, including two end segments secured respectively to the adjacent portions of the diving suit, and at least one intermediate segment, adapted to be nested in a predetermined angular relationship as the joint is flexed. The segments are interconnected by at least one gear and linkage assembly for distributing an angle of flexure of the joint in a predetermined proportion among the segments and for reventing the segments from separating. The compressive force of the surrounding water on the spherical segments is transmitted through at least one roller assembly.

This invention relates to articulated joints for a lowpressure diving suit, and more particularly to an improved form of articulated joint which maintains a constant displacement volume when flexed.

In a diving suit it is necessary to provide the wearer with an environment that will protect him and that will permit the accomplishment of useful functions. The articulated joints of the invention allow a mobility to the wearer which is comparable with that of a free swimmer, provide thermal protection to the wearer for long periods in cold water, and permit the air pressure in the suit to be maintained at a normal pressure of substantially one atmosphere.

In the prior art, numerous forms of articulated joints are employed for providing mobility to a diver. In the most common form of diving suit the joints form a part of a fabric suit attached to a rigid helmet. Protection from water pressure is afforded to the diver by maintaining the internal air pressure of the suit substantially equal to the external pressure. Subjection of the diver to extremely high air pressure has the disadvantage of a mandatory period of decompression when surfacing. A period of decompression limits the maximum operational period possible and prohibits immediate recovery of the diver in an emergency.

Some diving suits of the prior art employ joints which vary in displacement volume when flexed. A changing volume during fiexure, particularly in a low pressure suit, requires that the diver expend energy on the surrounding water in addition to the energy required to perform a desired task. I

Even in a suit using a constant volume joint, as the depth of the surrounding water increases, the joint may be incapable of carrying the increased load caused by the increased water pressure. Further, the increased water pressure may cause adjacent moving parts to bind due ice the foregoing and other disadvantages of the flexible joints of the prior art by providing improved constant volume joints which are completely flexible when subjected to pressure because auxiliary means are used to support the pressure load. The characteristics of the auxiliary means are such that friction between the parts is not increased with depth. In accordance with the concept of the invention, the constant volume joints comprise a pair of end segments, having the shape of spherical segments-of-onebase, with each contoured to form a port which adapted to receive the limb of a wearer; a plurality of ring-shaped intermediate spherical-segments-of-two-bases; a means for intercoupling the spherical segments to distribute the angle of movement of the joint among the segments and to carry compressive forces across the joint between the end segments; and a tubular section of flexible, non-permeable material, such asfor example-rubberized fabric, aflixed to each segment and circumscribing the intermediate segments to create a seal between the segments.

More specifically, a plurality of shells each having the form of a spherical segment, are interconnected to form a structure having the shape of a series of spherical segments of diminishing diameter, in which each segment is partially nested in the segment of next larger diameter. The segments are constructed to withstand compressive force and to maintain substantially constant volume when subjected to pressure. The segments are interconnected by gears and linkages so that, when a bending moment is applied to the joint, each segment rotates inside the segment of next larger diameter to permit the volume of the joint to remain constant throughout the range of fiexure. The gears function to distribute, in a predetermined proportion, the angle of fiexure of the joint, among the segments. The connecting linkages prevent the segments from separating. When the joint is immersed in a fluid, the pressure of the fluid on the joint tends to cause each segment to be enveloped in the segment of next larger diameter. Means for preventing the collapse of the joint in all relative angular positions of the segments, within the range of flexure, is provided by aflixing a pair of rollers to each of the alternate odd segments. Each roller in the succession is held in pure rolling contact with adjacent rollers to bear the force of the fluid. Force on the alternate even segments of the succession is transmitted by the connecting linkages to the load bearing rollers. When the joint is flexed, a lune-shaped surface area on one side of each segment, defined by two intersecting great circles, is enveloped beneath the surface of the adjacent next'larger segment. An equal lune-shaped surface area is exposed on the opposite side of each segment. Therefore, flexure of the joint does not change the surface area of the joint. Because of the symmetry of construction, provided by the spherical segments, the joint also maintains constant volume. Since the joint displaces a constant volume during fiexure, it may be flexed without expending human energy on the fluid creating the outside pressure. A pressure seal between the surfaces of each shell is provided by a flexible, non-permeable fabric which convolutes over the enveloped areas and covers the exposed areas of the joint. As the joint is flexed, the fabric convolutes between segments without friction.

It is, therefore, an object of this invention to enclose a human being in an environment having a first fluid pres sure, which environment is substantially constant pressure in the presence of surrounding higher fluid pressures.

It is also an object of this invention to allow movement of the enclosed human being without expending energy on the surrounding fluid.

It is a further object of this invention to improve constant volume joints for body-enclosing suits to reduce the energy expended by the wearer in moving the suit.

It is likewise an object of this invention to allow greater range of flexibility in the joints of diving suits.

It is also an object of the invention to provide for enclosing a diver or other person in a portable artificial environment corresponding to that existing at some relatively low altitude on the surface of the earth, which artificial environment is constant for any relatively lower depth and independent of the environment outside the suit.

It is an object of the invention to provide a diving suit adapted for use at great depths to maintain a substantially normal pressurized environment for the wearer.

It is an object of the invention to provide a constant volume diving suit adapted for use at great depths with flexible joint connections for facilitating maximum freedom of movement with minimum human energy expenditure.

It is an object of the invention to provide flexible joints which employ successive segments intercoupled to maintain the displacement of the joint substantially constant when it is subjected to pressure.

It is an object of the invention to provide flexible joints for withstanding compressive force when subjected to external pressure.

It is an object of the invention to provide flexible joints which maintain substantially constant displacement when flexed.

It is an object of the invention to provide flexible joints which employ successive segments intercoupled to prevent relative axial separation when a joint under pressure is flexed.

It is an object of the invention to provide flexible joints which employ successive segments intercoupled so that the angle of flexure is distributed into relative angular movement of the segments in a predetermined proportion.

It is an object of the invention to provide flexible joints which employ successive and interconnected segments for withstanding compressive force in any position of the joint Within a range of flexure.

It is an object of the invention to provide means for withstanding compressive force received in any direction within a range of operation.

It is an object of the invention to provide means for constraining relative angular displacement between structural elements to distribute, in a predetermined proportion, the angular displacement between said elements and for carrying compressive forces across said element.

The novel features which are believed to be characteristic of the invention, both as to its organization and method of operation, together with further objects and advantages thereof, will be better understood from the following description considered in connection with the accompanying drawings. It is to be expressly understood, however, that the drawings are for the purpose of illustration and description only, and are not intended as a definition of the limits of the invention.

FIG. 1 is a view of the typical suit utilizing the constant volume joints of the invention.

FIG. 2 is a profile view of a typical joint of the invention.

FIG. 3 is a view taken from the right in FIG. 2.

FIG. 4 is a view, partly in profile, partly in section, taken at 44 in FIG. 3 which shows the joint in a fixed position.

FIG. 5 is a view of the joint in an alternate position.

FIG. 6 is a fragmentary view, partly in profile, partly in section, taken at 6-6 in FIG. 5.

FIG. 7 is a view of a typical gear train and roller asselmbly.

With reference now to the drawings, wherein like or corresponding parts are designated by the same reference characters throughout the several views, there is shown in FIG. 1 a constant volume suit which includes, as an interval part thereof, a plurality of constant volume joints, according to the invention. Substantially the same proltection to the wearer is provided by the joints as by the rigid portions of the suit. The joints also allow mobility compatible with the anatomical range of movement of the man inside.

As shown particularly in FIGS. 2-5, the constant volume joint of the invention comprises-for examplefive basic structural elements, namely: an upper spherical end segment 10 connected to an upper adjacent element 11 (see FIG. 1) of the suit at an upper port 20 to move with the enclosed body member; a lower end segment 18 connected to a lower adjacent element 19 (see FIG. 1) of the suit at a port 22 to move with the enclosed body member; a plurality of annular shaped inter-mediate segments connected between the upper and lower segments 10 and 18 to permit the flexure of the enclosed body members by a partial nesting, in the direction of flexure, of each segment inside its adjacent next larger segment; sealing means 24, which is a flexible non-permeable material, for sealing the interstices between the segments 10, 12, 14, 16, and 18; and means 29 for regulating angular travel of the segments and for carrying compressive forces across the joint.

In order to facilitate an understanding of the invention, consideration will be given first to the manner in which the simultaneous rotations of segments 10, 12, 14, 16, and 18 (in FIG. 4) duplicate the angle of flexure of the enclosed body members, then to the manner in which fabric 24 provides a pressure seal between the respective segments, and then to the means 29 for distributing the angle of flexure of the enclosed body members over the angular displacement between adjacent segments and for carrying compressive forces across the joint.

Angular motion of the enclosed body members is duplicated in the joint by the simultaneous rotation of each nested segment through an angle equal to a predetermined fraction of the total angle of flexure. Each equal segment is connected to rotate within a range of movement inside the next larger, adjacent segment. Because the segments have a spherical shape, each segment rotating inside another must have a common center of curvature with the larger segment. In 'order to achieve the desired range of flexure in the joints, the segments are spaced to make the sum of the angles of rotation of each segment with respect to the next larger segment equal to the total angle of flexure. The odd segments in the sequence (10, 14, 18) are spaced so that each of the respective centers of curvature (13, 15, 17) rotates with respect to each adjacent center of curvature. The displacement between odd segments is bridged by even segments in the sequence (12, 16) which are spaced at midpoints between centers of curvature 13, 15 and 15, 17 respectively, and which segments each have an inner surface with a center of curvature common to its next small er adjacent segment (14 and 18 respectively) and each have an outer surface with a common center of curvature with its adjacent next larger segment (10 and 14 respectively). When the joint is flexed through an angle defined by the relative positions of axes 21 and 23, the center of curvature 13 rotates with respect to 13 and the outer 17 rotates with respect to 15 through one-half of the angle of flexure. Each segment 12, 14, 16, and 18, rotates inside the next larger segment through an angle equal to one-fourth of the total angle of flexure.

Fabric 24, shown particularly in FIG. 4, provides a sealing means between segments 10, 12, 14, 16, and 18 in all positions of the joint. Fabric 24 extends from end segment 10 to end segment 18 to enclose the external surfaces of intermediate segments 12, 14, and 16. Pressure forces fabric 24 into the minimum displacement permitted by the supporting structures of segments. Fabric 24 convolutes on one side of the joint (see 24a) between the areas of each segment, which are subtended by the next larger segment, and the corresponding subtending areas of the next larger segment. On the other side of the joint (see 24b) fabric 24 is pressed over areas of segments not subtended by adjacent larger segments. When the joint is flexed, the outside pressure causes the fabric 24 to assume a minimum volume, whereby the fabric moves in a rolling motion from one position to another. Its extreme positions are shown in FIG. 4. To maintain the distribution and alignment of the fabric 24, portions of the fabn'c which should not move may conveniently be fastened (for example, by gluing) to a portion of each shell. When the joint is flexed outwardly from the wearer, areas of fabric are rolled, from a position covering the outer surface of a particular segment (for example 24b of FIG. 4), to a position covering the inner surface of the corresponding subtending segment (for example, 24d of FIG. 5). On the extending side of the joint, fabric 24 is rolled from the subtending inner surfaces (for example, from 24a of FIG. 4) to the surfaces of the extending, adjacent smaller segments (for example, 24c of FIG. 5). Fabric 24 is everywhere supported by the segments except for those ring-shaped unsupported areas between and perpendicular to the surfaces of adjacent segments. Fabric 24 provides a pressure seal for these unsupported areas.

Means 29 regulates relative motion of segments 10, 12, 14, 16, and 18 to distribute the total angle of flexure of the joint into relative angular movement of the segments, to prevent compression by the external fluid of each segment into the adjacent larger segment, and to prevent separation of each segment from adjacent segments. Means 29 is one of a pair of substantially identical gear train and roller assemblies. Means 29 comprises a first means for transmitting compressive forcesupper roller 30with a first driving meansgear 48-rigidly attached at one end, intermediate means for withstanding compressive forces-intermediate roller 36-with a second driving means-gear 50and a third driving meansgear 58 (not shown in FIG. 4)-rigidly attached at opposite ends, and third means for transmitting compressive force-lower roller 38-with fourth driving meansgear 60rigidly affixed at one end, first connecting meansupper linkage 40and second connecting meanslower linkage 42. Upper roller 30 and intermediate roller 36 are held in rolling contact by upper linkage 40. Intermediate roller 36 and lower roller 38 are held in rolling contact by lower linkage 42. Compressive forces applied to upper roller 30 and to intermediate roller 36, for example, cancel at the line of contact. Separation between upper roller 30 and intermediate roller 36, for example, is prevented by upper linkage 40. First gear 48, aflixed to upper roller 30, meshes with second gear 50, aflixed to one end of intermediate roller 36, third gear 58, aflixed to the other end of intermediate roller 36, meshes with fourth gear 60, afiixed to one end of lower roller 38. The sequence of first gear 48, upper linkage 40, second gear 50 having a colineal axis of revolution with third gear 58, lower linkage 42, and fourth gear 60 comprises a planetary gear train. Each element in the sequence is rotatable with re spect to adjacent elements. For example, rotation of the entire shown gear train through an angle is accomplished in the following manner. Angle 6 represents the angular difference in the position of the joint shown in FIGURE from the position of the joint shown in FIGURE 4. More particularly, angle 0 represents the angle through which line 21 of FIGURE 4 moves as the joint is moved from the position shown in FIGURE 4 to the position shown in FIGURE 5. Assume fourth gear 60 to be fixed. Lower linkage 42 rotates through an angle A with respect to fourth gear 60. Third gear 58 and rigidly attached second gear 50 rotate an angle A with respect to lower linkage 42. Upper linkage 40 rotates through an angle A with respect to second gear 50 and rigidly attached third gear 58. First gear 48 rotates through an angle A with respect to upper linkage 40. Thus the rotation of the gear train through an angle 0, or 4A, is distributed inpredetermined proportions over the displacement between adjacent elements in the gear train.

Consider now the manner in which means 29 is constructed for distributing angular movement and for withstanding the force of external pressure.

As shown in FIG. 2 a plurality of rollers (30, 36, and 38) are in contact to carry compressive forces across the joint. Referring now to FIG. 6, it can be seen that each roller has at least one bearing positioned about the axis of the roller. First bearing 49 is mounted in upper roller 30. Second bearing 51 and third bearing 52 are mounted at opposite ends of intermediate roller 36. Fourth bearing 53 is mounted at one end of lower roller 38.

Gears are rigidly aflixed to the rollers to rotate therewith about common axes. First gear 48 is connected to upper roller 30, second gear 50 and third gear 58 to opposite ends of intermediate roller 36, and fourth gear 60 to one end of lower roller 38. The gears are attached to the rollers by screws (FIGS. 4 and 5) for example, screws 54 and 55 connect third gear 58 to intermediate roller 36. The pitch diameter of each gear is equal to the diameter of the roller to which it is attached. Alternative means of attachment are press-fitting of the gear on the roller, or machining the gear from the roller blank as an integral part.

Linkages connect adjacent rollers in frictional contact while permitting angular movement of the rollers and gears with respect to the connecting linkage. Upper linkage 40 and lower linkage 42 each comprise a bar and pin connecting means (FIG. 6). Upper linkage 40 is connected to upper roller 30 by insertion of the pin 39 into first bearing 49 mounted in upper roller 30. Pin 41, at the opposite end of upper linkage 40, is inserted into second bearing 51 of intermediate roller 36. Lower linkage 42 connects intermediate roller 36 and lower roller 38 by insertion of the pins 43 and 44 into third bearing 52 and fourth bearing 53 respectively.

Gears connected to adjacent rollers are meshed to distribute relative angular movement of rollers 30, 36, and 38 in a predetermined fashion. First gear 48 on upper roller 30 is meshed with second gear 50 on intermediate roller 36. Third gear 58 rotates with second gear 50 because both are attached to an intermediate roller 36. Third gear 58, on intermediate roller 36, is meshed with fourth gear 60 which is mounted on lower roller 38. In the embodiment shown, the relative angular movement between the rollers 30 and 36 of one pair of adjacent rollers is made equal to the relative angular movement between the rollers 36 and 38 of the other pair of adjacent rollers by utilizing substantially identical gears in the chain.

It should be noted at this point that for simplicity of description only the gear train in one embodiment of the invention is shown in FIGS. 4-7. It will be understood from the description set forth above, however, that the invention encompasses the use of one or more planetary gear trains intercoupled in accordance with the teachings herein disclosed, and that the number of gears and linkages employed in any given device will be determined by the angle of flexure to be duplicated by the joint. A gear train of minimum length includes at least two end gears and one connecting linkage.

Consider now the manner in which the elements of the joint are connected. Each gear and linkage is connected to a different segment of the joint to distribute angular rotation. Gears are rigidly connected to consecutive odd segments in the sequence (10, 14, 18). End gears are rigidly connected to upper end segment 10 and lower end segment 18 respectively. It will be recalled that each gear is connected to a corresponding roller. Each roller is connected to a segment by means of a bracket (for example first gear 48 is connected to upper roller 30). Upper roller 30 is connected to bracket 26 by screws 34 and 32. Bracket 26 is mechanically connected to the interior of upper end segment 10. Linkages are rigidly attached to consecutive even numbered segments. Upper linkage 40 is connected to intermediate segment 12. Lower linkage 42 is connected to intermediate segment 16, for example, by screws 45 and 46.

In operation, when donning the suit, if the joint is for examplean elbow joint, the wearer inserts his arm into port 20 (shown in FIG. 2). The arm emerges from port 22. Port 20 and port 22 connect to adjacent members of the suit to completely enclose the elbow of the wearer.

When the suit with the enclosed wearer is submerged, a pressure dilferential, that is proportional to the depth, exists between the interior of the suit and the external water pressure. The internal air pressure of the suit is maintained at substantially one atmosphere.

The force of the hydrostatic pressure, which is constant over the surface are-a of the joint, is borne by the rigid spherical shells 10, 12, 14, 16, and 18, by the load-bearing plurality of rollers 30, 36, and 38, and by fabric 24. The force exerted by the Water is perpendicular to the surface at every point on the surface. For purposes of analysis, the force on every infinitesimal area of the surface may be thought of as a vector which may be resolved into component parts in particular directions. In order to illustrate the action of the load bearing rollers, axes may be chosen along lines joining the centers of curvature 13 and 15 and joining centers 15 and 17, as shown by FIGS. 35. The force on each infinitesimal area of each segment has a component in the direction of each line joining the centers of curvature and a component in a plane perpendicular to this line. Forces in the direction of lines joining the centers of curvature 13, 15, and 17 tend to collapse each segment into the adjacent next larger segment. The forces are transmitted from end segments and 18 to rollers 30 and 38 by brackets 26 and 28, respectively, in each of the identical pair of means 29. Rollers 30 and 38 transmit the force to roller 36. Forces on intermediate segments 12 and 16 (which are connected to a pair of upper and lower linkages 40 and 42 respectively) are transmitted by the connecting linkage to each of the identical pair of rollers 36. The interconnected rollers and linkages are constructed to support the force across the joint while maintaining their planetary relationship. Compressive forces due to component force vectors located in a plane perpendicular to the lines joining the centers of curvature 13 and and joining centers 15 and 17 are not transmitted to the system of rollers and linkages but are Withstood by the rigid construction of the spherical shells. Forces are also exerted on the ring-shaped areas of fabric which seal the interstices between the spherical segments. The force on the fabric is less than the tear strength of the fabric because the area of fabric not supported by a rigid segment is very small. The magnitude of the force is equal to the pressure multiplied by the area subjected to the pressure. The size of the unsupported area is made minimal by establishing a minimal difference in the diameters of adjacent concentric spheres. Only that separation necessary to permit the fabric to convolute is allowed. Forces on the fabric which exist at the operating depth of the joint are maintained at a safe level below the tear strength of the fabric because a very small area of fabric is subjected to the force. There is no translational movement of a segment into a larger segment. Nor does the applied force cause the joint to exhibit an angular movement. Thus, when the joint is subjected to pressure, it remains in equilibrium.

Force exerted on the suit by the bending of the wearers arm causes the joint to rotate. Flexure of the wearers arm causes the enclosed body member to exert force on the inner surface of the suit. The direction of this force is perpendicular to axis 23 shown in FIG. 4. If the force supplied by the wearer is of a magnitude sufficient to overcome friction, the joint rotates. Force applied by the wearer to a suit member 19, connected to port 23, acts about the axis of rotation through 17 of the pair of fourth gears 60 of lower end segment 18. Force acting about an axis at a distance constitutes a torque. The application of a torque to each end gear 60 of the pair of gear trains is transmitted to each successive gear in the respective trains. The rotation of fourth gear 60 transmits an equal torque to third gear 58 while it rotates about third gear 58. Second gear 50 transmits an equal torque to first gear 48 while rotating about first gear 48. Each gear and linkage of means 29 is connected to a different segment to distribute angular rotation. The pair of first gears 48 attached to upper end segment 10 remain stationary. Gears 48 comprise the sun gears in the pair of planetary gear trains. The succession of rollers moves in the planetary relationship of the gears without slippage. Each roller is attached to at least one gear to connnect the gear to a segment.

Rotation of the gears by application of a torque to the rain causes the succession of rollers to move with the gears. Because the diameter of each roller is equal to the pitch diameter of each attached gear, the rollers are constrained to move without slippage. The segments are thereby interconnected to distribute and constrain angular flexing of the joint into angular movement of adjacent segments in a predetermined proportion. As the segments rotate, fabric 24 convolutes between adjacent segments to form a pressure seal for the ring-shaped areas not supported by the segment.

The forces created by water pressure on the joint are at equilibrium during rotation of the joint. The system of rollers and linkages withstands force in every position of the joint within a range of flexure. The compressive force on each segment is constant at a particular depth because the constant surface area of that segment is exposed to the external pressure.

The diver expends no energy on the surrounding water in flexing the joint. When the joint is rotated through an angle, a lune-shaped surface area described by two intersecting great circles on a particular segment, is enveloped. An equal lune-shaped area on the other side of that segrnent is exposed. This is true for each nested segment and, therefore, the surface area of the joint remains constant as the joint is rotated through an angle. The volume of water displaced by the joint is equal to the sum of the volumes displaced by each spherical segment. Upper end segment 10, for example, contributes to the total displacement. Each segment that protrudes from the next larger segment contributes additional volume to the total displacement. The volume displaced by a particular segment is the function of the surface area of the segment exposed to the pressure differential and of the radius of the spherical segment. The surface area of each segment has been shown to be constant as the joint is rotated. The radius of each segment is made constant by construction. Therefore, the volume displaced by any particular spherical segment is constant as the joint is rotated. The total displacement of the joint, equal to the sum of the displacements of each segment, is also constant as the joint is rotated. If the volume of the joint remains constant, there can be no displacement of Water when the joint is rotated. The amount of energy expended is equal to the force applied multiplied by the distance through Which it acts. Force due to pressure is present, but because there is no displacement of the force through a distance, the product indicates that no energy is expended on the surrounding water when the joint is rotated.

The joint ceases to rotate when the wearer ceases to apply force to the joint or when a limit of travel of the joint has been reached. A specific embodiment of the invention shown is capable for flexure through an angle of It is to be understood, of course, that various alternatives and modifications could be made to the constant volume joint herein disclosed without departing from the invention. For example, additional spherical segments could be added by extending the pair of planetary gear trains to provide a larger angle of fiexure. Accordingly, it is to be expressly understood that the spirit and scope of the invention are to be limited only by the spirit and scope of the appended claims.

What is claimed as new is:

1. An articulated, segmented joint for a protective suit, having end ports defining two axes, said axes being adapted to be substantially aligned with body axes of an enclosed member comprising:

a plurality of juxtaposed circumferentially continuous segments, including at least two end segments and at least one intermediate segment, said segments adapted to be nested, in sequence, with said end segments having end ports defining two axes which are adapted to be aligned with the body axes of an enclosed member;

flexible, non permeable material sealing the interstices between said segments; and

means for constraining relative angular displacement between all said segments, in all positions of said joint, to distribute the angular displacement between said axes in predetermined proportions to all said segments, said means being constructed to carry at least substantially all compressive forces across said joint between said end segments.

2. A device as recited in claim 1 in which said predetermined proportions are one to one.

3. A device as recited in claim 1 and further comprising stops for limiting the angular travel of said joint.

4. A device as recited in claim 1 in which said means for constraining relative angular displacement between said segments simultaneously rotates each said nested segment through an angle equal to a predetermined fraction of the total angle of flexure of the joint.

'5. A device as recited in claim 1 in which said flexible, non-permeable material sealing the interstices between adjacent nesting, moveable segments is connected between the external surfaces of said end segments to enclose said intermediate segments.

6. A device as recited in claim 5 in which said flexible, non-permeable material rolls from the outer surface of the retracting side of each said moveable segment to the inner surface of the adjacent large subtending segment and rolls from the inner surface of each said segment to the outer surface of the adjacent extending segment.

7. A device as recited in claim 1 in which said means for constraining relative angular displacement and for carrying forces across said joint comprises two substantially identical planetary gear train-linkage-roller assemblies, the first and last gears of each said assembly being connected to said end segments to turn therewith, and each gear and linkage of each of said assemblies being connected to a different said segment to distribute the angular rotation between said end segments across the junctions between said intermediate segments and the junctions between said intermediate segments and said end segments.

8. A device as recited in claim 1 in which said means for constraining angular displacement comprises:

a pair of substantially identical gear trains, connected to control flexure of said joint and connected to said segments to distribute and constrain angular flexing between adjacent sections in a predetermined proportion, and supporting torque applied across said joint.

9. A device as recited in claim 8 and further including linkages and rollers, connected to said gears of said gear train, to support forces between said end segments.

10. A device as recited in claim 9 in which said gear trains each have a plurality of consecutive gears including at least two end gears, and have at least one connecting linkage, adjacent meshing gears being attached to said linkages to constrain said gears against relative displacement and to support forces directed between and perpendicular to the rotation axes of said gears.

11. A device as recited in claim 10 in which said segments are odd in number, said linkages are rigidly connected to the consecutive even said segments, said gears are rigidly connected to the consecutive odd said segments, and said end gears are rigidly connected to said first and last segments.

12. A device as recited in claim 11 and further comprising:

a plurality of shafts rigidly connected to said gears, including end shafts connected to said end gears, with two gears on each said shaft and one gear on each said end shafts, each of said gears meshing with only one other adjacent said gear.

13. A device as recited in claim 12 and further comprising a plurality of rollers, equal in number to said shafts, mounted upon said shafts in rolling contact to carry compression forces between and perpendicular to the rotation axes of adjacent shafts.

14. A device as recited in claim 13 in which each of said rollers on each said shaft, having two gears thereon, is positioned between said two gears on that particular shaft.

15. A device as recited in claim 8 in which said pair of substantially indentical gear trains are positioned on and attached to said segments at opposing ends of diameters of each said segment.

16. An articulated, segmented joint for a protective suit, having end ports defining two axes, said axes being adapted to be substantially aligned with body axes of an enclosed member comprising:

an odd number of juxtaposed circumferentially continuous segments, including at least two end segments and an odd number of intermediate segments, said segments having substantially spherical surfaces nested, in sequence, with said intermediate segments having a substantially annular shape and said end segments having end ports defining two axes which are adapted to be aligned with the body axes of an enclosed member;

flexible, non-permeable material sealing the interstices between said segments;

a pair of substantially identical planetary gear train and roller assemblies for constraining relative angular displacement between all said segments distributing, in predetermined proportions to all said segments, the angular displacement between said axes, each said gear train and roller assembly including linkage means therebetween, the first and last gears of each said assembly being connected to said end segments to turn therewith, and each gear and linkage of each of said gear trains being connected to a different said segment to distribute the angular rotation between said end segments across the junctions between said intermediate segments and the junctions between said intermediate segments and said end segments, said pair of gear train and roller assemblies being constructed and arranged to carry substantially all compressive and tensional forces across said joint between said end segments; and

stops for limiting the angular travel of said joint.

17. A device as recited in claim 16 in which said means for constraining relative angular displacement between said segments simultaneously rotates each said nested segment through an angle equal to a predetermined fraction of the total angle of flexure of the joint.

18. A device as recited in claim 16 in which said flexible, non-permeable material sealing the interstices between adjacent nesting, moveable segments is connected between the external surfaces of said end segments to enclose said odd number of intermediate segments.

19. A device as recited in claim 18 in which said flexible non-permeable material seals the interstices between adjacent nesting, moveable segments.

20. A device as recited in claim 19 in which said flexible non-permeable material rolls from the outer surface of the retracting side of each said moveable segment to the inner surface of the adjacent larger subtending segment and rolls from the inner surface of each said segment to the outer surface of the adjacent extending smaller segments when all said segments are angularly moved relative to each other.

21. A deep sea diving suit in which the pressure within the suit is to be much less than that of the surrounding water, comprising:

a first portion of the suit adapted to enclose one member of the human body;

a second portion of the suit adapted to enclose an adjacent member of the human body which is connected to the first member of the body by a joint;

a diving suit joint interconnecting said first and second portions of the suit, said suit joint including two end circumferentially continuous segments secured respectively to said first and second suit portions, and further including at least one circumferentially continuous intermediate segments, said segments having substantially spherical surfaces adapted to be nested in sequence with the intermediate segments having substantially annular shape;

flexible non-permeable material sealing the spherical surfaces between said segments;

means for constraining relative angular displacement between said segments to distribute, in predetermined proportions in any position of said joint, the angular displacement between said suit portions over the angular displacement between adjacent segments; and

means for carrying at least substantially all the high compressive forces across said suit joint between each of said segments.

22. A suit as defined in claim 21 wherein the means for carrying the compressive forces constitute cylindrical surfaces, and wherein the angular distribution means constitute gears secured to the compressive force carrying means.

23. A suit as defined in claim 21 wherein an odd number of segments are employed in the suit joint.

24. A gear train and roller assembly comprising:

a planetary gear train having a plurality of consecutive 12 gears including at least two end gears and at least one connecting linkage;

a plurality of shafts rigidly connected to said gears, including end shafts connected to said end gears, with two gears on each shaft and one gear on each said end shafts, each said gear meshing with only one other adjacent gear;

a plurality of rollers, equal in number to said shafts, mounted upon said shafts in rolling contact with the rollers of adjacent shafts to carry compression forces between and perpendicular to the rotation axes of said shafts; and

means for maintaining said gears in meshing contact.

25. A device as recited in claim 24 in which said rollers on each shaft, having two gears thereon, are axially positioned between said two gears on that particular shaft.

References Cited UNITED STATES PATENTS 396,773 1/1889 Smith 285114 568,537 9/1896 Laubsch 285-1 14 685,628 10/1901 Morris 285184 X 1,349,060 8/1920 Gall et al. 22.1 X

1,383,322 7/1921 Marr 285264 X 1,722,375 7/1929 Hipssich 22.1 3,236,544 2/1966 Brown 285261 X 3,242,499 3/ 1966 Fonda-Bonardi 22.1

FOREIGN PATENTS 402,272 11/1909 France. 422,037 3/1910 France.

CARL W. TOMLIN, Primary Examiner.

D. W. AROLA, Assistant Examiner.

U.S. Cl. X.R. 

